Rattananukrom T.Arenas R.Ramírez Y.Luz Ely Guevara-Cerritos A.Hernandez-Castro R.Mahidol University2025-08-152025-08-152025-08-01Skin Health and Disease Vol.5 No.4 (2025) , 297-302https://repository.li.mahidol.ac.th/handle/123456789/111639Actinomycetoma is a chronic, progressive bacterial infection characterized by granuloma formation, with Nocardia vulneris being a rare causative agent. A 32-year-old healthy man from El Salvador presented with painless nodules, scars and discharging sinus tracts on his back. Examination of the exudate revealed small white grains, and Nocardia species were isolated through culture. Molecular identification of N. vulneris was confirmed via 16S rDNA gene amplification and sequencing. The patient was treated with trimethoprim-sulfamethoxazole and dapsone, resulting in significant clinical improvement after 6 months. He continues on this treatment regimen. This case highlights the rarity of N. vulneris mycetoma at an unusual anatomical site and demonstrates the effectiveness of combined trimethoprim-sulfamethoxazole and dapsone therapy.MedicineArticleSCOPUS10.1093/skinhd/vzaf0412-s2.0-1050125653602690442X